“On the Nature of Things” Book 4 by Lucretius (1st Century BC)


  • I’m just trying to experience all there is in the world
    • All in order to teach others, to remove the bonds of religion & brace the reader for unpleasant truths that will cause him to recoil & reject them


  • Pictures of things & thin shapes emitted from things off their surfaces & form an appearance of the thing
    • the image floats off it in light like smoke off a burning log
      • Some are denser & darker than others
    • Some show the image from the object’s core & surface
      • Includes color, shades, shapes, heat, smell, smoke, all which diffuse at different rates depending on the depth of the source within the object


  • Some things are so small that they can’t be seen at all
    • You cant distinguished their parts
    • But they’re so thin that when you rub them, they’ll give off a small that proves their existence


  • The air is able to cause constant changes to their appearance – shades, colors, shapes, etc.
    • Clouds float by in different forms, colors, sizes, etc.
    • Rocks & mountains look different at different times of the day


  • They come about, change & go away at different speeds
    • We’ve seen how quickly a sunny day can turn to overcast & then completely dark
    • When looking at the sky, the things in the air that transform color, shade, etc. must travel very fast to be able to change & be apparent to us on the ground far below
    • Smells can travel across a great distance as well as cold & heat from its sources to us far away


  • In the dark we can feel the shape of an object but in the light, our sense of sight kicks in from the image of the the thing, not the thing itself
    • idols of things are carried around & the image tells us distance, color, shape, etc.
      • The thing moves the air toward our eyes to perceive it
      • The more air around to move, the more we see of a thing
      • It gives a collective image/feeling, rather than many individual images
  • The images of a thing on the other side of a door are showed to us but the door is showed stronger
    • However, the image will go around the door allowing us to see it but only in a dispersed form
  • Mirrors tend to swap sides with the images in them
    • Things on the right will appear on the left & vice versa
    • Things come at us at the same angle they are shown to us in the mirror
  • Bright things cause us to turn our eyes away, just as the sun does because the brightness of the light on the object is reflected back into our eyes with the same intensity it’s sent with
    • The black air of darkness is dispelled by the light
    • It doesn’t work the other way around because a shadow & darkness is purely the absence of light
    • We see something constantly because the light is shining on it constantly. Once the light stops, our sight of the thing stops


  • There are things we see that just aren’t so
    • In a boat, we may seem like we’re still & it’s the land that’s moving
    • Stars look fixed in the sky but they are really moving
    • Children spin around & around, & when they stop, the world appears to them to spin more
    • The world fools our vision due to our mental suppositions that just don’t square with reality


  • If you believe nothing is known or can be known, then where do you even start to learn, understand & to know?
    • Senses provide us with our first glimpse of what’s true
    • Although they may be fooled from time to time, senses applied to reason will give us knowledge
    • Trust each sense to its own domain & power
      • One will tell you what it saw, another what it heard, etc.
    • Use them with reason to give you knowledge of the world

520- 612

  • Sound & voice make their way to the ears
    • Voice goes through the throat & out the mouth
    • it has the power to hurt since it’s an exertion
      • Try shouting for a while & see how it feels…
    • Through his voice, a man loses a part of himself
  • The less the distance between the speaker & the listener, the more distinguishable each syllable is
    • Further away, words become more difficult to understand
  • Voices don’t go directly to the ears but are sent past them & picked up – some are lost in air
    • They can bounce off rocks & sound like several voices at once
  • They say where satyrs & nymphs live, voices & noises break the silence with pipes & singing that people can hear from miles away
  • Voices can travel though solid objects
    • Conversations can be hear through doors because sound is sent in many directions but images only in one direction


  • We perceive taste when we chew, squeezing out the flavor, which works its way around the mouth & tongue
  • Pleasure comes from all this swishing around
    • Once it slides down the throat, the pleasure is gone
  • Different foods are pleasant & nutritious in different ways
    • Some are nauseous & bitter to some, & pleasant & sweet to others
  • The seeds of things are mixed in them in many ways
    • Since so many things differ on the outside, they also differ inside of the taster, as well as the thing itself
      • Explains why things are bitter & gross to some & not to others
        • Because it matches their nature


  • Smells affect us by the flows streaming in & out
    • Like taste, many things please some & not others
    • Smells can drive animals like dogs crazy
      • Different smells have different effects
    • Some smells carry farther than others but as the smell carries, it disperses & won’t be as strong or as concentrated, & eventually fade to nothing


  • Some animals are distressed by different sights, sounds, smells
    • Hungry lions do not like to see a rooster crowing & flapping its wings around in the morning
    • It hurts their eyes & ears


  • These idols wander around in many ways & directions & unite together, entering through the eyes & going to the mind
    • We see all sorts of visions floating through the air such as Centaurs, Scylla’s limbs & Cerberus-like faces of dogs
      • We don’t actually see centaurs because they’ve never existed
    • But when visions of a man & a horse together they stick because of this nature of visions


  • Seeing with the mind is very similar to seeing with the eyes
    • In the mind’s moved to see a lion, by way of idols, it will see a lion


  • The mind’s intelligence still works when we sleep & is provoked by these same idols
    • We see people who’ve been dead for quite some time, among other things.
    • Our memories sleep & are often contradicted by the things in our dreams


  • Why is it that man thinks of a thing after he’s wished for it?
    • Do these idols check our wishes & pop them into our minds?
    • They can take over our minds & make us think all kinds of thoughts at any time of the day or night
  • Many times we can see something & it’ll stay in our minds passively & come to the forefront of our minds when we want – sometimes when we don’t want
    • They’re waiting right now but they’re so thing that the mind has to strain to see them
    • That’s true of many things that are even right next to you in reality
  • The mind takes many visions & sometimes draws the wrong conclusions by by the meshes of self-delusion
    • A woman may look like a man, a young person may look old, etc. if seen from a certain, deceiving angle


  • Men ought to cast aside any ideas that the world is custom-made for us & the shapes of all things are divinely inspired
    • Natural things aren’t born for some purpose but a purpose is found in what is already there after it is born
    • Seeing & hearing didn’t exist before the advent of eyes & ears
    • The tongue was around before any language & limbs were around before they were of any use


  • It’s in the nature of the body to require food
    • Particles withdraw from the body through breathing, working & sweating, & they need to be replaced
    • Food & drink restore everything missing from the body
    • Hunger dies off once the craving is satisfied


  • Let’s talk about how our wills can make our bodies move
    • Idols walking become present in our minds & then the will to walk arises
    • No movements happen in the body without a will to move
    • When the mind stirs the will & the force of the soul spreads throughout the body to walk
    • The body moves like a machine with inter-connected parts drive by a single force


  • Sleep allows the body to rest & the mind to be calm
    • Takes place when the force of the soul is scattered about the body – the body goes limp when it goes to sleep
    • The force of soul is there just no concentrated
  • The exterior of the body is exposed to air
    • This is why so many things have a rough exterior to deal with the rough air outside & inside when the body breathes
  • A part of the soul is forced out during breathing & another part is drawn in
    • After a lot of this, the force of the body is scattered throughout the body & needs to be restored through sleep
  • When a man has exerted himself in his activities, these activities cloud his mind as he sleeps
    • But they also remain in his mind when he’s away
    • These dreams have a way of coming about when he’s not asleep
  • Animal will go through motions as they sleep, sweating, barking & crying out
    • The nastier the animal, the nastier the behavior during sleep
  • Dreams also take form representing the things we find important, what we want & what we fear


  • When we become ripe in age, we become sexually aware & our libido & sexuality control the body & the mind
    • Our see swells from within & moves toward the object of desire
    • Often love is a greater weapon a man’s soul than a physical wound is to the body


  • Love distracts your other passions & you can’t think on anything else
    • It becomes a disease & even those who aren’t in love long to catch the disease
  • Venus compels us to feel pain when our love is away & causes us to burn with desire when our love is near
    • Nothing can satisfy the craving
    • When people make love, they are overcome by desire for pleasure & the madness continues


  • It’s a waste of strength & labor to be obsessed with love
    • Duties neglected & reputation falls apart
    • Every positive becomes miraculous & a cause to celebrate & every negative becomes a cause for sorrow


  • Love causes the appearance of things to change in our view depending on what side of it you’re on
    • We see the object of our love as a goddess as our minds transform them into something supernatural
    • When we are on the wrong side of love, the illusion is shattered & we are in great pain


  • Women aren’t immune to this either
    • How else would people & animals be around?
    • Those in mutual pleasure are tortured in their common chains because we can’t even want to be on our own


  • When a woman mixes her seed with a man, children come from this sharing of part of the traits of the mother & father
    • Sometimes they can resemble their grandparents in appearance & personality
    • Resemblance can cross sexes – sons can look like their mothers, daughters can look like their fathers


  • Men have a great desire to impregnate their wives & will go to great lengths to do so if there are problems conceiving
    • They pray & sacrifice to the gods for children
    • It depends on the quality of the seed
    • Some men can conceive with some women & not others
    • A woman is said, that being on all fours to be more likely to conceive but to do so is what whores do to try not to get pregnant


  • Beauty isn’t everything with love
    • Good manners & personality work as well
    • Custom plays into attraction because of the charm of pleasant habits a woman will have toward a man. He’ll cave eventually

Leave a Reply